The present invention relates to an apparatus having a blower fan, in particular to a manually-guided portable blower, a combination vacuum device/blower, or the like.
Manually-guided blowers generate an air stream by means of a motor-driven blower fan. The air stream is directed to the desired application by means of a blower tube that extends from the blower fan. Such blowers are carried, for example, on the back, and are manually guided, and in this connection are used to blow fallen leaves into a pile. A vacuum or suction operation is also possible with a vacuum tube that is placed upon the intake opening of the blower fan. The blower can also be used as a sprayer, whereby material to be sprayed, such as a plant protection agent or granular material, is introduced into the blower tube. If such a blower has a venturi device and a collection bag, it can also be used as a nut collector or the like. The housing of the blower fan, the blower wheel, and in particular the blower tube are made of polymeric material which acts as an electrical insulator relative to the drive motor, which forms an electrical ground.
At an appropriate blower capacity, a relatively high flow velocity flows in the blower tube. This can lead to electrostatic charges under appropriate atmospheric conditions, and when dirt or dust particle laden ambient air is drawn in, in particular due to friction between the particles as well as with the fan wheel, the fan housing and with the wall of the blower tube. Contact with components of the blower can lead to undesired electrostatic discharges.
It is therefore an object of the present invention to improve a blower of the aforementioned general type in such a way that the formation of an electrostatic charge is prevented.